Patent Literatures 1 to 4 describe techniques of detecting the presence or not of dangerous substances such as explosives and narcotics in baggage at the boarding gate of airports, ports or the like. Patent Literature 5 describes a technique of changing the pressure of fluid in accordance with the shape and dimensions of a target object.
Patent Literature 1 describes a trace detecting system that moves a joint, thus moving a nozzle in accordance with the outer shape of a detecting target to blow compressed gas on the surface of the detecting target at the rate of the air velocity of 20 m/s or more. Patent Literature 2 describes a trace detecting system including a nozzle that blows compressed gas on the surface of a detecting target at the rate of the air velocity of 20 m/s or more, thus blowing the compressed gas to the inner wall of a collecting section as well as an arm holding the nozzle. Patent Literature 3 describes a technique of making an inspector wipe out the surface of baggage with a wiping member and determining the presence or not of a dangerous material and the type of it on sample microparticles attached to the wiping member. Patent Literature 4 describes a technique of including a sampling head that extends over the overall width of a sampling chamber to store baggage, the sampling head including a rotary brush to sweep the exposed face of the baggage and brings such a sampling head into contact with the surface of the baggage using a spring, a sensor or a servo, thus collecting sample microparticles attached to the surface of the baggage. Patent Literature 5 describes a spraying system to dynamically determine the fluid pressure (fan-air pressure, atomizing air pressure and the like) corresponding to a moving target object or a part of a moving target object, and capable of dynamically varying the liquid discharge pattern from a plurality of nozzles held at a common header.